A liquid crystal display (LCD) panel includes scan lines and data lines that cross each other. The data lines are controlled by a data driving chip. When the data driving chip receives a data activating signal TP1 (latched pulse), the data driving chip outputs a data voltage to the data lines of the LCD panel at a negative edge of the TP1. The scan lines are controlled by a scan driving chip arranged on two sides of the LCD panel. Currently, the scan driving chip that controls a positive edge and negative edge of each scan line of an LCD requires three control signals: a start pulse signal STV (start voltage pulse) that controls a start of a first scan line, a clock pulse signal CKV (clock voltage pulse) that is sent a shift register of the scan driving chip to control switching frequency of each of the scan lines and start to act when the STV is detected to be at a high level at a positive edge of the STV, and an output enable control signal OE (output enable). Because the LCD panel comprises a parasitic capacitor, scan output voltage (out) is delivered into the LCD panel, which causes a time delay. Because of the time delay, there is a time delay between the positive edge and the negative edge of the scan lines, thus forming, an overlapping, time region between the positive edge and the negative edge of the scan lines, which makes data signals of the data lines be in the wrong position (as shown in FIG. 1). Because the OE is at a high level, output voltage is forced to be reduced, if the OE is arranged between the positive edge and negative edge of the scan lines, adjacent scan lines are forced without forming simultaneously overlapping time regions, which avoids overlapping opening time of two lines and making the data signals of the data lines be in the wrong position, as shown in FIG. 2.
The control signals of the scan driving chip are transmitted to a glass of the LCD panel by a printed circuit board assembly (PCBA) via a flexible circuit board of the data driving chip, then transmitted to the scan driving chip by a glass cabling. Currently, a main design of the LCD panel is developed towards a narrow frame, however adding a signal is that one more wire is cabled on the glass, which occupies space of an edge of the glass makes a sequence control chip T-CON (timing controller) need one more control signal and increases cost.